Second, installing a home automation system will likely require investments in bridges, which are separate pieces of hardware that connect with home routers. But in time, this may be an unnecessary expense.

Third, the market is filled with vendors taking shots at one another's wireless technology. There will likely be some disruption as protocols are sorted out and settled on.

Behind the scenes, groups and vendors are promoting a range of machine-to-machine wireless communication protocols, including Z-Wave, ZigBee, Insteon, Bluetooth Low Energy and new arrivals such as the Weightless standard. These are protocols that enable devices, light bulbs, thermostats, door locks, wireless speakers, security systems, lawn sprinklers and sensors of all kinds to talk with one another.

Features these wireless protocols all have in common are low energy and low bandwidth requirements, the goal being to extend battery life for as long as years. Most use mesh networks that enable devices to pass signals to one another, extending network range, reliability and redundancy. Wi-Fi is a big part of this, too, and cellular technology will be as well. Each has role to play in connecting things.

We're still in the early days of the IoT and, to be fair, it's important to note that device makers are being forced to make bets in an immature environment. But at this point, no one has made a bad bet.

For instance, in 2009, Schlage introduced a wireless locking system with a clever TV commercial showing a man using a BlackBerry to unlock his front door while he was miles away from his home.

Schlage developed its innovative locking system after realizing that the locks of today will not be the locks of tomorrow. That development effort led to a later spin-off, Nexia Home Intelligence.

There are now more than 200 home products that can be controlled through Nexia's bridge. Those products rely on wireless communications protocols that use a bridge or a hub to connect to a home network router. The bridge makes it possible for people in or out of the house to monitor and control devices via smartphones or PCs. The Nexia Bridge retails for about $60 and requires a subscription that costs $9.99 a month.

Nexia supports Wi-Fi and Z-Wave, a technology the company believes is best for its deployments. That means that people whose homes have products that use ZigBee, for instance, will need a separate bridge.

Matt McGovern, marketing manager at Nexia, says the company is agnostic about communications protocols and is watching the market. If Nexia has to expand protocol support, using the cloud as a bridge to other protocols is a possibility. But for now, "we know what works for us and what works for customers," he said.

The communication protocol that may get the most attention over the next two years is Bluetooth Low Energy or Bluetooth Smart, its marketing name.

One potentially disruptive technology could come from CSR, a semiconductor company in Cambridge, England, that announced in February that it had developed a mesh technology for Bluetooth.

Paul Williamson, CSR's director of low-power wireless, said the intent was to expand Bluetooth Smart capability beyond just a few devices to broad network of them, allowing a single smartphone or set-top box to address "thousands of nodes within a large building infrastructure."

In principle, "there is no need for a bridge if you are directly in the environment controlling the device," said Williamson.

What drives the need for bridges is a desire to give people the ability to control products from a distance, such as when they're at work or on the road. But even in that case, Williamson doesn't believe consumers will necessarily have to purchase separate bridges; he expects bridges to more likely be something like set-top boxes or other devices that already exist.

Indeed, the companies that may have the biggest impact on home networking are familiar ones. Cable TV set-top box providers could embed home automation radios in their devices. (In 2012, Comcast said it was incorporating ZigBee technology.) Google could do that in Chromecast. And router makers could support the technologies.

To control costs, these vendors may set a limit on how many wireless radios they support in set-top boxes and routers, but it's possible for hubs to support multicommunications devices. Smart Things, in its hub, includes support for both Z-Wave and ZigBee.

Frank Gillett, an analyst at Forrester Research, said the fundamental question is whether any of the communication protocols out there "do anything dramatically different" from what LTE, Wi-Fi or Bluetooth Smart do.

All these technologies are in smartphones, which ship by the billions, Gillett noted. "The question is [whether] there's room for anything else to survive," he said.

Whether CSR Mesh, as it's called, turns Bluetooth into a mesh that competes directly with Z-Wave or ZigBee remains to be seen.

Then there's Insteon. In addition to being a wireless network, it also offers power line communications that send data over existing power wiring. "When you combine power line and radio in a mesh network like we have [done], that reliability is dramatically different," said Dan Gregg, CTO of Insteon.

There is a degree of trash talking or at least pointed criticisms by the various vendors.

ZigBee officials, citing their open standard, dismiss rival Z-Wave as "more of a user group for Zensys," which developed the Z-Wave communications protocol. Sigma Design bought Zensys and now licenses the technology.

Meanwhile, an official of the Z-Wave Alliance is similarly dismissive of ZigBee, and says device makers using ZigBee will implement it in different ways, creating incompatibilities. ZigBee, in response, says it runs a certification program to ensure uniformity.

For its part, CSR, in its Bluetooth mesh announcement, pointed out the shortcomings of both ZigBee and Z-Wave.

"From a networking perspective, the IoT is a mess and will remain so," said Nick Jones, an analyst at Gartner. "I expect for the next few years more than 10 wireless technologies will get significant traction in IoT applications."

There's no perfect technology. Challenges include the cost of the hardware, with cellular being the most expensive. And then there are issues such as operations costs, bandwidth, range and architecture to consider. Different applications have different requirements and different needs, said Jones.

"The first problem is there is no single wireless technology that optimizes all of these for all situations," he said.

The compatibility of the data interchange is another problem.

"Even if two devices share the same wireless, they may not share the same communications protocols. I expect we'll see lots of islands," Jones said. "Will a Samsung microwave talk to a Bosch washing machine, a Phillips smart light bulb and a Siemens smart electricity meter? Probably not for a while."